10MHz vectron OCXO help

  • Hello all,
    Greetings. I need help to make an 10MHz ref clock for HackRF-one SDR(TX radio).

    Today salvaged one Vectron (C4710C1-0023 10.000000MHz 12700-01371 0737) OCXO from a broken VSAT modem main board. It has 5 pin:

    1: EFC - Electronic Frequency Control input
    2: Reference voltage output
    3: RF Out
    4: GND
    5: Vs

    Here is the datasheet: https://www.vectron.com/products/ocxo/C4710.pdf
    (I cant find if it is HCMOS or Sinewave out from the part numbers.)

    This is my first time playing with an OCXO - so not clear how to use this. From different project by other hams I think I need to put Vs (12V), and set the EFC to 2.5v(or should i make it 0 by connecting to gnd?) derived from the reference voltage output using a multiturn potentiometer. Please advise if I am correct?

    Thanks, S21RC

  • Hi,

    It seems the OCXO provides a 5V output derived from 12V input. Make this Output adjustable with a multiturn potentiometer and feed the voltage to pin1 . This way you can control the frequency - or have some smart circuit like a gpsdo do it for you.

    Here is a circuit , not exactly your OCXO but you get the idea: Control Voltage

    Please note that the pinout pins 3 , 4, and 5 in my example is different.

    73, Martin